Suppose I have a failed tx in the object store - is there some tool I can use to load in the "tx-object-store" directory (or just one of the data files in there) to tell me things about the transaction that failed (can it tell me what datasource(s) were involved? what SQL? when it happened?). I just want to do some debugging - anything I can learn about the failed tx would potentially be helpful to me.

As it stands, I see my tx-object-store has files in it, but obviously those files are all opaque and you can't tell anything about them.

There is a swing app that provides a front end to the object store, but the information is not particularly rich. In particular the store contains no association between the xa resource and the datasource it comes from, nor the business operations associated to its transaction. At least not in the current release. For EAP 4.x you'll need to download the corresponding TS release to get the tooling. For EAP 5 its in docs/examples/transactions, packaged up as an app that can be deployed into the server.